Arrangement for generating an electric corona discharge in air

• US 4,976,752 A
• Filed: 04/10/1990
• Issued: 12/11/1990
• Est. Priority Date: 09/26/1988
• Status: Expired due to Fees

• Current Assignee: Astra Vent AB
• Original Assignee: Astra Vent AB
• Inventors: Torok, Vilmos, Loreth, Andrezej
• Primary Examiner(s): Nozick, Bernard
• Application Number:
  US07/506,736
• Time in Patent Office: 245 Days
• Field of Search: 55/117, 55/120, 55/150-153, 55/138, 361/230
• US Class Current: 96/43
• CPC Class Codes: B03C 3/38 Particle charging or ionising stations, e.g. using electric discharge, radioactive radiation or flames
• CPC Class Codes: H01T 19/04 having pointed electrodes

Abstract

An arrangement for generating an electric corona discharge in air having a corona electrode, a target electrode which is spaced from the corona electrode, and a d.c. voltage source, the respective terminals of which are connected to the corona electrode and the target electrode. The voltage of the voltage source and the construction of the corona electrode are such as to generate a corona discharge at the corona electrode. A conduit is provided for continuously removing the air present in the immediate vicinity of the corona electrode and dealing with the air thus removed in a manner to render innocuous physiologically harmful substances or irritants present in the air and generated by the corona discharge, such as primarily ozone and nitrogen oxides.

Claims

1. An arrangement for generating an electric corona discharge in an airflow path which is in communication with a human environment and continuously removing harmful gases produced as a consequence of the corona discharge from the airflow path, comprising:

a duct having an airflow therethrough;

a corona electrode, and a target electrode spaced from said corona electrode in said airflow of said duct downstream of said corona electrode as seen in the direction of said airflow;

a d.c. voltage source having first and second terminals to which said corona electrode and said target electrode, respectively, are connected, the voltage between said terminals of said voltage source capable of creating a corona discharge at said corona electrode;

piping means to continuously remove harmful gases produced as a consequence of said corona discharge, extending from inside said duct and out of said duct, and including a pipe with an orifice at one end thereof;

said orifice of said pipe facing in the downstream direction of said airflow and towards said target electrode, and said corona electrode being located substantially centrally in said orifice, and said pipe over the remainder of its length being hermetically sealed relative to said airflow in said duct;

an air pumping means connected to said pipe for generating a flow of air into said pipe through said orifice closely past said corona electrode.

2. An arrangement as claimed in claim 1, wherein an opposite end of said pipe is open and communicating with free ambient air at a location separated from said human environment.

3. An arrangement as claimed in claim 1, wherein a purifying means for removing said harmful gases from a flow of air through said pipe is connected to an other end of said pipe.

4. An arrangement as claimed in claim 1, wherein said corona electrode comprises a short needle-like element oriented substantially axially in said airflow in said duct and said orifice is substantially circular.

5. An arrangement as claimed in claim 1, wherein said corona electrode comprises an elongated wire extending across said duct and said orifice has a narrow, elongated rectangular shape.

6. An arrangement as claimed in claim 1, wherein said pipe is electrically conductive or semi-conductive at least in the proximity of said one end and is connected to an electric potential close to the electric potential of said corona electrode.

7. An arrangement for generating an electric corona discharge in an airflow path which is in communication with a human environment and continuously removing harmful gases produced as a consequence of the corona discharge from the airflow path, comprising:

a duct having an airflow therethrough;

a corona electrode, and a target electrode spaced from said corona electrode in said airflow of said duct downstream from said corona electrode as seen in the direction of said airflow;

a d.c. voltage source having first and second terminals to which said corona electrode and said target electrode, respectively, are connected, the voltage between said terminals of said voltage source capable of creating a corona discharge at said corona electrode;

piping means to continuously remove harmful gases produced as a consequence of said corona discharge, extending from inside said duct and out of said duct, and including a pipe with an orifice at one end thereof;

said corona electrode comprising a short needle-like element oriented substantially axially in said airflow in said duct;

said orifice of said pipe being substantially circular and facing in the upstream direction of said airflow and being located substantially in axial alignment and opposite to said needle-like corona electrode element, and said pipe over the remainder of its length being hermetically sealed relative to said airflow in said duct;

an air pumping means connected to said pipe for generating a flow of air into said pipe through said orifice.

8. An arrangement as claimed in claim 7, wherein an opposite end of said pipe is open and communicating with the ambient air at a location separated from said human environment.

9. An arrangement as claimed in claim 7, wherein a purifying means for removing said harmful gases from a flow of air through said pipe is connected to another end of said pipe.